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<!DOCTYPE topic
  PUBLIC "-//OASIS//DTD DITA Composite//EN" "ditabase.dtd">
<topic id="topic1">
  <title id="cw20941">DROP PROTOCOL</title>
  <body>
    <p id="sql_command_desc">Removes a external table data access protocol from a database.</p>
    <section id="section2">
      <title>Synopsis</title>
      <codeblock id="sql_command_synopsis">DROP PROTOCOL [IF EXISTS] <varname>name</varname></codeblock>
    </section>
    <section id="section3">
      <title>Description</title>
      <p><codeph>DROP PROTOCOL</codeph> removes the specified protocol from a database. A protocol
        name can be specified in the <codeph>CREATE EXTERNAL TABLE</codeph> command to read data
        from or write data to an external data source.</p>
      <p>You must be a superuser or the protocol owner to drop a protocol.</p>
      <note type="warning">If you drop a data access prococol, external tables that have been
        defined with the protocol will no longer be able to access the external data source.</note>
    </section>
    <section id="section4">
      <title>Parameters</title>
      <parml>
        <plentry>
          <pt>IF EXISTS</pt>
          <pd>Do not throw an error if the protocol does not exist. A notice is issued in this case.
          </pd>
        </plentry>
        <plentry>
          <pt><varname>name</varname></pt>
          <pd>The name of an existing data access protocol.</pd>
        </plentry>
      </parml>
    </section>
    <section id="section5">
      <title>Notes</title>
      <p>If you drop a data access protocol, the call handlers that defined in the database that are
        associated with the protocol are not dropped. You must drop the functions manually. </p>
      <p>Shared libraries that were used by the protocol should also be removed from the Greenplum
        Database hosts.</p>
    </section>
    <section id="section6">
      <title>Compatibility</title>
      <p><codeph>DROP PROTOCOL</codeph> is a Greenplum Database extension. </p>
    </section>
    <section id="section7">
      <title>See Also</title>
      <p><codeph><xref href="CREATE_EXTERNAL_TABLE.xml#topic1"/></codeph>, <codeph><xref
            href="CREATE_PROTOCOL.xml#topic1"/></codeph></p>
    </section>
  </body>
</topic>
